


Unthinkable

by Levi8



Series: Consequences of Thermodynamics [1]
Category: The Flash (TV 2014)
Genre: Episode: s01e15 Out of Time, Episode: s01e23 Fast Enough, Gen, Pseudoscience
Language: English
Status: Completed
Published: 2021-01-18
Updated: 2021-01-18
Packaged: 2021-03-15 05:07:03
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,711
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28807806
Author URL: https://archiveofourown.org/users/Levi8/pseuds/Levi8
Summary: Post Flashpoint alternative scene in episode 23 of season 1.When Cisco goes to talk with Doctor Evil about the temporal shearing problem, he sure as hell wasn't expecting Eobard to attempt explaining reversed entropy distribution let alone why killing Cisco now was unthinkable when he'd so easily done so in a different timeline.
Relationships: Cisco Ramon & Eobard Thawne | Harrison Wells
Series: Consequences of Thermodynamics [1]
Series URL: https://archiveofourown.org/series/2113200
Comments: 2
Kudos: 10





	Unthinkable

**Author's Note:**

> Please excuse the nonsensical pseudoscience in which my headcanon of time travel relies on why this exchange is so different post Flashpoint from the one we had in season one. 
> 
> All original dialogue belongs to CW
> 
> I use Thawne in the original scene and use Eobard where I diverge from canon.

"Something on your mind, Cisco?"

"No…"

Thawne waited Cisco out, looking over the schematics wondering how he could have missed this.

"Yes."

There it was.

"How did you fit your Reverse-Flash suit into that little ring? Is it some sort of compressed micro tech?"

He looked up from the schematics and smiled sadly, he was going to miss this. That hadn't been the question he'd been expecting though. Then again Cisco often found ways to surprise him.

"Or actually, forget it. I don't care…" Thawne looked back at the schematics, not surprised at the dismissal of interest but not wanting to face it, knowing what had to be done. Fifteen years of planning and a future he belonged to said as much.

"Maybe a little." Thawne ignored the comment.

"Ronnie's right. I should have accounted for the temporal shearing."

"Glad we're still good for something." Thawne looked up mildly incredulous that the young man thought his mind was less valuable to him as Eobard than to him as Wells.

"I never underestimated your contribution, Cisco." The cold stare he was met with had him once again looking at the schematics. "Or Ronnie," He included. Thawne took a breath, wanting very much to reassure the boy in front of him. It shouldn't matter, but it did.

"As a matter of fact, do you know how many times I wished you were there with me as I rebuilt the accelerator? It would have been a lot more fun." He smiled and looked back down at the time sphere schematics once more to verify what needed doing while trying to reign in the needling desire to smooth things over.

"Yeah. Well, doesn't change the fact that your nifty little Time Sphere..."

"Is that what you're calling it?" He knew damn well that what he was calling it, that's what was on the schematic. He just… He needed to assert himself, this was his initial design, one he'd just figured out how to fix. Cisco raised his voice just a little,

"... Whatever it's called. It's gonna blow." Thawne looked back up to deliver his verdict.

"Not if you cement the tiles with a cobalt resin. That'll prevent degradation in conditions of extreme heat." He raised the papers up and smirked lightly.

"Okay. Fine. We'll try that." Cisco turned around without another look leaving Thawne nonplussed.

"That's it? That's all?" He'd been expecting more than that, he'd expected a chance to explain himself.

Cisco rapidly turned back around, almost like he'd wanted to stay, but hadn't had a reason. The quick turn came with a raised and demanding voice.

"Well, what do you want me to say?" Cisco walked back as Thawne threw the schematics to the side in frustration at himself and at Cisco.

"I dont know, Cisco. I thought that of anyone, you'd be a little more understanding of my predicament." He was angry now and walked right up to the glass. "I don't belong here. These barbaric times." He sighed and turned around. "It's like living amongst the dead." Thawne rested his hand against the back wall, almost resigned.

"Is that what you told yourself? When you killed me?"

Thawne turned his head back towards Cisco, concerned and shocked.

"What?" It was quiet. Quieter than he had meant it to be. "What did you say?" Thawne turned back towards Cisco and crossed his arms, not entirely sure, but nonetheless fearing what Cisco meant.

"It was an alternate timeline. One that Barry reset," Thawne knew what he was talking about, though he'd gone out of his way to make sure that Barry didn't tell him any more than he already had. He'd impressed upon him how important it was to not change things, but change things he had. Thawne had felt those changes reverberate through the Speedforce. He didn't know what they were, but he had known that he had personally changed somehow.

"But I never forgot it. It just kept coming back to me. And I can still picture the way you looked at me when you called me a son." Thawne closed his eyes then, realizing what he had done. Who he had created. "And you crushed my heart..." He opened his eyes knowing what was in Cisco's future, what he'd be subjected to, who he'd become. "With your fist."

"Cisco..." His emotions were overwhelming him, knowing his end. "I'm sorry."

"Yeah. It sucked."

"No, you misunderstand me. I'm not apologizing for killing you. I can't."

"Oh. Oh you can't, can you?" Eobard paused again tempering his resolve. If anyone deserved to have an inkling of how the universe compensated for speedsters, it would be Vibe. He stepped forward, arms still crossed.

"Hear me Cisco, for just a few moments." Cisco walked forward just a bit before stopping himself. "One of the most interesting and chaotic effects when traveling through time, something specific to speedsters, is the inexplicable ripples that emanate from both the point in time a speedster enters a rupture in the time-space barrier and the point in time they leave it.

"It's difficult to explain but… the actions taken between the exit and the entry date may not have occurred yet, but they still leave an emotional - residue, if you will, on both future and past actions.

"All powerful emotions can cause a disturbance but regret - regret is a powerful thing Cisco." Eobard took another small step forward, pleased when Cisco matched him, his intrigue clearly piqued.

"If someone had made a choice between the start date and the end date that resonated regret beyond themselves to the point of causing a temporal reverberation, then any speedsters passing by that moment in the wrong entropic direction could then go about things the exact same way, and still end up with a very different outcome when others do not act as they had before." He waited a moment as he watched Cisco thankfully taking the time to consider what he was saying despite how he was clearly feeling.

"So what, speedsters time traveling to the past drag the localized entropy levels of the present back with them?"

"Yes! Exactly." Eobard uncrossed his arms a smile on his face as he took the last step forward that he could. It was no wonder that the universe chose Cisco to be Vibe. It was no wonder when he picked these complex ideas up and made them manageable.  
  
"The timeline is malleable, entropy is not. That chaos has to go somewhere so the further back in time a speedster travels, the further back beyond the exit point in time that chaos spreads." He paused again as Cisco's attention seemed to fade, looking beyond him rather than at him.

"Wouldn't things have already been different then when you traveled back a few centuries, do you even have a home to go back to?" Eobard couldn't help but smile, nodding, rocking back on his heels.

"When Barry saves his mother I will indeed have a home to return to. Things will still undoubtedly be different. But that's a price I'm willing to pay." That seemed to focus Cisco on the present once more.

"If you knew all this then why… Why do it in the first place?" Eobard sighed, suddenly feeling drained.

"Ask Barry what I tell the Flash after I meet you for the first time, with my true face."

"What?" Eobard shook his head with another sad smile, and took a step back, arms crossing once more, returning to the matter at hand. The apology he couldn't give.

"Cisco, I can't apologize for killing you, because the man that killed you is, rather was, a completely different entity than I am. If he did it I'm sure he had a good reason; He wouldn't have done it if he didn't. But the regret he felt after, that made me something, someone, else entirely when Barry ran back, accident or not.

"If I'd ended up in whatever situation he had, I doubt I would have killed you. Hid you maybe, taken you someplace else, I don't know. But killing you is unthinkable to me. Just you... and Caitlyn. I don't have that revulsion at the thought of killing anyone else, I could probably look at just about anyone else in this time and think of them as already dead, yes. But not you."

"What about Barry?" Of course he'd ask that.

"Before he knew who I was, if I hadn't needed him, maybe. After watching him grow up though... It's irrelevant regardless. I need him alive to get me home." Cisco took another step forward, the closest he had been since his incarceration.

"Sooo if you weren't apologizing for another version of yourself killing me…?" 

Ah… what could he say about what he had done to his dearest student without giving too much away. He took another step back, leaning on the back wall again.

"I'm sorry for the fact that you are able to retain traces of another timeline. You're able to see through the vibrations of the universe. It means…

He paused for a moment letting it really sink in. He'd wondered sometimes…

"I wasn't sure until just now."

"Sure of what?" Cisco took the last step he could towards the glass separating them. A victory, if only a small one. One that didn't ultimately matter.

"The night the particle accelerator exploded, you were affected too."

"What are you talking about? No, I wasn't." Cisco took a step back shaking his head. Thawne looked at the young man in front of him, really looked at him.

"Don't be afraid, Cisco. A great and… Honorable destiny awaits you now. I only hope that as you're living your great adventure, that you remember who gave you that life. And that it was given out of love."

Cisco looked at him with an incomprehensible look on his face. And turned away and walked out. Thawne didn't try and stop him again, he'd said his piece. He was just glad that Cisco had seen fit to hear him out. Unfortunately that unnerving need to smooth things over hadn't been quelled in the slightest. Thawne supposed he'd just have to suppress it, he'd be home soon anyway. None of this would matter then. Absolutely none of it.


End file.
